Process of reducing magnesium compounds



L. WALDO.

PROCESS 0F REDUCING IVIAGNESIUNI COMPOUNDS.

APPLICATION FILED JULY 31.1920.

Patented May 31, 1921.

LSTQ@ autres 4srarus nnaif-infn orifice.

Lnonann'fwa'fnno, orrnain'rinnn, lNew Jansz?.

l riaocnss or Bienvenue montieren coimouivns.

Lacasse.

Specification oi. Letters Patent.

Application tiled July 31, 1920. Serial No. 400,554.

To all whom t ma/ z/ com-m. s L Be it known that L 'LnoNARD WALno, a citizen of the United States and resident of 'llainfield in the county of Aof New Jersey, have invented certain new and useful Improvements in Processes Yof Reducing Magnesium Compounds, of which the following is a specification. 4 My invention has for its objectto provid a sim le, efiiclent and economical method of re ucing magnesium compounds to the metal magnesium; and more particularly the reduction of magnesium oxid to magnesium by the use of aluminum. According to the preferred mode of practising my invention finely-divided, magne- A sium oxid and finely-divided metallic aluminum 1n their roper molecular'pro or-I tions are thorough y and intimately mixed mechanically 1n any approved manner, such, for example, as b operations employed in the mixing of exp osive powders. The mixture 1s compressed into compact bodies, such as tablets, balls, or the like, by any known or approvedmeans in order to insure a close conglomeration ofthe particles of the two materials, .and also to provide interstices I among the assembled bodies. Such bodies are introduced in a retort and subjected to ``a temperature of about 1100 C. to 1350 C. @a vacuo, with some such reaction as is indicated in the following equation:

' Ihe reaction begins at about 900 C. and its rapidityincreases as the temperature rises. Under' the condition of intimate contact in the pulverulent state and at high temperature 4n oalcuo the oxid of magne sium' gives u its oxyeln to the contiguous aluminum, 'orming z,Op (andI poibly other little known 'oxids 0f fhlminuin) and' 2Union and State can be heate ture. The tube is provided with a thermocouple 6 and the galvanometer 7.

' being used in subsequent operations for the recovery of magnesium from viously described.

he magnesium oxid' and the aluminum should bewvery'finely comminuted (sep- Mg() as prearately) and most thoroughly mixed, and the two materials should be solidly compressed before subjecting the mixture to the heating operation in vacuo abovel described, as otherwise no substantial reaction will be had. The division of the compacted materials intotablets, balls, or like units, 'provides, throughout the charge within the retort a multiplicity of interstices for the free exit of the magnesium vapor.

The operation can be eficiently conducted vin an a paratus of the character illustrated re 1 is a dia-Y inthe awings; wherein Fi gram of the apparatus, and ig. 2is a longitudinal vertical section of an electric resistance furnace and charged retort.

The particular form of electric resistance furnace shown comprises a tube 3 of high melting point metal, such, for example, as chromel) or nichrome, supportedl within a suitable insulating casing 4. Wound about this tube throughout its length is a. coil 5,-

preferably of platinum, which is 'electrically connected with a. source of electric energy of hi h vol whereb the tube tothe esired hig tempera- A retort, comprising a metal tube 8 hermetically closed at one end 9,. is adapted to Patented May 31,1921.

seA 1 be snugly entered in the furnace tube. The I other end ofthe retort is provided with a -l suitable coupling 10 for one end of .a rela-xv tively lon -tube 11 which.` constitutes accondenser; he outerend of the -tube A11 1s -connected by means of a pipe' 12 with an exhaustin pump 1.3, referably of the continuous oi type, whic is geared with and operated by an adjacent' motor 14. The pump, when the parts are assembled, is

operatedto exhaust the retort and condenserA and establish .therein a high de ee of vacuum. The pipe leading to t e pump is equipped with a vacuum gage 15-and with suitably-disposed stop-cocks, such as 16, 17.

In practising my invention' the retort, charged with the above described bodies comprising MgO and Al, is introduced in the furnace tube. cou led to the 'retort and the pump is actuate until the desired high degree of vacuum The condenser is then.

lie-steen in tlie eeteet and cene deesse. dene9 die eeel F3 adjacent tine ente? ed tiie eoiiailensei1 closed; tlie o pemtion of tliegmmgo is stepped, and time misent is delivered Vto tine femme time end continued 'time contents of the etoi't subjected to tine action o a tempeetise ed tent 135W G. ft eet-no, which temgeeiefmie is meinte-med the metal Mg iles ieeen over into the cendense'Y-es" atome deseiibed, beine accomplished 'A 1 l tbe meteifttogetne die condense?9 is :ifomtlie :'mneee; the eetoift and condenseiae sepeieted from eecii other lay mempiiietien of the compiling, and tiie' een- Seeed eziieustin@ jepeiatien et theimmp een lie continued dm-"img the piecess oi" Ifednetien.' Y

ift to nndesteod tine-t tte-deem et aieove Vdeseiilzed is iiinstmtive i Y meijdeee 'eomli'eimd to metallic magnesium, which compmses timely dividing seid compound;

fneiy dividing metallic aluminum; intimately mixing the nely divided materiels;

closely compnctimg the mixture under pifes- Seite? end snlijecting tlhe consolidated meteiieis to' the action of efhigli degreeiof lient dit ebano, with the formation sind distillattion over oit tlie metal magnesium'.

2, A process ot reducing e'mzrgnesium exid toV metallic magnesium, .which eem@ piises intimeteiy mixing nely divided megnesinm oxid amd timely divided silmrmimim9 compressing tlie mixture 4inte compact liodies, and subjecting the seid bodies to tlie ection et e, high-degree ot heet zwfvecum witlitiie formation :md distillation over' et tiie metal magnesium. A n

3. A peocess et reducing emsignesmm oxid to metallic magnesium, which" comprises intimately mixing nely divided megnesimn oxid end nely divided eluminnm, compressing tlie mixture Iinto compact bodies, and subjecting'tlne seidloodies to tlie action of e temperature from about iitl1l C. to-elbout 135W C. it www. l v l Signed et New York, inltlie county'end State ont New vYoili, this 30th .dey of dimlyo A. n.- ieee. i

temmen Winoo; 

